When we first encountered the problem, someone hinted that the two sides converged in a “Y” before entering the tank, and that caused more splashing and thus foam. When I eventually got a decent look at things, the configuration met what Fred describes above... no “Y”.
I’ve learned to accept the longer fill times associated with low speed pumps. Cleaning up the mess that usually results with high speed trucker pumps wipes out any fill time they might save anyway. They are made for neck-free saddle tanks where there’s no choke point for foam to build up in, and where the user can see the fuel level. I only use the high speed pumps if there’s no other option. I have to go slower using them, which doesn’t always sit well with on-the-clock truckers lined up behind me.
Joel